Vent plug



A. H. SNYDER Oct. 4, 1938.

VENT PLUG Filed Jan. 8, 1937 Patented Oct. 4, 1938 l UNITED STATES PATENT oFFicE VENT PLUG Almond H. Snyder, Lancaster, N. Y., assigner to National Battery Company, St. Paul, Minn., a corporation of Delaware Application January 8, 1937, Serial No. 119,576 1 Claim. (Cl. 251-147) This invention relates to ventplugs, particuopen position when the vent isA in its` normal larly although not exclusively, adapted for the or substantially upright position. The weight I1 storage batteries of aircraft or for other service normally rests on a head I8 formed on a valve where liquid containers must be vented and are stem` I9 and on a slotted seat 23 formed in the 5 likely to be inverted or tilted through a large body 1, as hereinafter more fully described. As 5 angle of departure from the normal, upright poshown in Fig. 3, the stem I9 is fluted longitudisition. nally so that its horizontal section is substantially It is my object to provide a novel and more cross-shaped and the head I6 is drilled from reliable vent plug for containers of such liquids top to bottom to provide passages 20. The stem l0 as evolve gas and for use where it is important I9 is slidable in an inlet 98588.88 2| extending l0 to guard against the escape of the liquid when up from the lower end of the vent body 1 and the container is inverted or tilted beyond a prethe head I8 is movable in an enlargement of determined angle. this passage communicating with the chamber A further object is to provide a vent plug of I I. The ball weight I1 is prevented from closthis class with a valve and operatingmechanism ing the Passage t0 the Chamber l l by the forml5 so constructed and located that certainty of option of slots 22 in a seat 23 for the ball I1, these eration is promoted, tests and inspections to slots being formed by drilling the seat 23 at suitdiscover defects or failure to operate properly able intervals, as shownin Fig. 6. are facilitated and replacement of the valve is The lower end 0f the Stem I9 rests on a ilexalso facilitated. ible and elastic valve comprising a diaphragm 20 The invention will be best understood by ref- 24 adapted to close the passase 2l when the erence to the accompanying drawing in which: weight I1 is removed from the head I8. The

Figure 1 is a central vertical section through diaphragm 24 is preferably constructed from my improved vent plug, taken partially on the thin, soft rubber or other elastic and acid-rez5 line I-I of Fig. 2; sistant material. As shown in Figs. 1 and 2. 25

Fig. 2 is a bottom view of the plug; it has a series of slots 25 cut through it and Fig. 3 is a bottom view of the valve actuating spaced from the axis of the plug to afford passtem and head; sages for gas when the valve is open, the central Fig. 4 is a. plan view of the plug; and portion of the diaphragm being imperforate to Figs. 5 and 6 are sections taken on the lines close the passage 2l when freed of the weight so 5-5 and 5-5 respectively of Fig. 1, the ball I1. To secure the diaphragm 24 on the lower weight having been removed to show parts otherend of the vent body, I provide a thick rim 26 wise concealed in Fig. 6. which is sufficiently elastic to snap into an an- 'I'he plug has a main body portion 1 of gennular groove formed near the lower endof the erally cylindrical form, constructed from acidbody I0, as indicated in Fig. 1. 35 resistant insulating material, such as hard rub- In use, the gas evolved from the electrolyte or ber. A threaded portion 8 near the normally from other liquid in the container to which my lower end of the body 1 is provided to fit the device is attached escapes freely through the slots usual or suitable opening in the cover of a bat- 25, passages 2i and 20 and slots 22 into the cham- 40 tery or other container, a washer 9 being prober II and thence escapes through the slots IB 40 vided to seal the connection. A central portion and outlet I3. The design of the several passages I0 of the body 1 has a knurled or otherwise is such that any condensate, which forms from roughened surface to facilitate manipulation. the gases or vapor within the plug, flows back into Within the body of the plug is a trap chamber the battery or other container. The'valve 2l II closed at the top by a screw cover I2 which remains open for this normal operation as long 45 is bored axially to provide a small outlet openas the container and plug are retained in the ing I3. This opening communicates with the normal, upright position or within a predeterchamber II through a nipple Il. Beneath the mined angle of departure therefrom, such that nipple Il and spaced slightly therefrom is a bafthe weight I1 remains on the head Il of the valve fie disk I5 having slots I6 (Figs. 1 and 5) at stem. 50 suitable spaced intervals around its periphery. The weight I1 is so proportioned relative to the These slots allow the escape of gas to the outlet diameter of the seat 23 that the valve is held opening Il. open until the device is tilted to such angle as to Within the chamber II is a weight I1, prefcreate danger oi' the escape of the electrolyte erably of spherical form, to hold the valve in through the vent plug. When this point is 55 reached, the weight I1 rolls off its seat 23 and releases the valve stem I8, whereupon, due to the elasticity of the diaphragm 24, the latter moves to the dotted line position indicated in Fig. 1 to close the passage ZI and prevent the escape of the electrolyte or other liquid from the container, Because of my arrangement of the baille disk I5 and nipple I4, the condensate which forms in the plug cannot escape through the vent openings I3 even when the device is inverted.

My device is positive in its action and effectively prevents the escape of the electrolyte even when used on the batteries of aircraft which are operated in inverted position and tilted to such angles as to allow the escape of the electrolyte in the absence of efficient valves in the vent plugs. Further advantages are secured by the location of the valve diaphragm on the exterior of theplug where it can be readily inspected, tested and replaced when necessary. Another feature of my device is the construction which insures free escape of the gases even in the event of failure of the valve diaphragm. The chamber for the head I8 is so designed as to maintain the passages 20 at all times in communication with the passages around the stem I9 and the seat for the ball weight l1 is so constructed as to prevent closure of the passages at this point.

Having described my invention, what I claim as new and desire to protect by Letters Patent is:

A vent plug comprising, a hollow cylindrical body having axially disposed inlet and outlet passages communicating with its lower and upper ends respectively and formed at its normally lower end with a reduced, tubular extension adapted to project through an opening in the cover of a battery or other container tobe vented, a. valve comprising a thin, elastic diaphragm capping the lower end of said tubular extension to close said inlet passage, said valve having apertures therethrough, oiIset from the axis of said body, a stem for actuating said valve movable in said inlet passage and formed with a head on its normally upper end to prevent removal of said stem downwardly through said inlet passage and a weight movable in said body and normally resting on said head for operating said stem to extend said valve to open position, said weight being arranged to release said stem and permit the closing of said valve upon the tilting of said body through a predetermined angle of departure from the vertical.

ALMOND H. SNYDER. 

